second entity query is executed with errors - sql

Question

I have 2 linq queries. First query does nothing because of unique index and this is OK. But second also does nothing while it should add records . If I bypass first query second query works. Should I refresh entity ? How ?
foreach (var product in productList)
{
cc2nexo_SubiektProduct newproduct = new cc2nexo_SubiektProduct();
newproduct.Name = product.Name;
newproduct.VAT = product.VAT;
newproduct.Id = product.Id;
foreach (var stawkaVAT in myNexo_ExitoEntities.StawkiVat)
{
if (stawkaVAT.Stawka * 100 == tryconvert_dec(newproduct.VAT))
{
newproduct.VAT_Id = stawkaVAT.Id;
}
}
myNexo_ExitoEntities.cc2nexo_SubiektProduct.Add(newproduct);
SurroundWithTryCatchDB(() =>
{
myNexo_ExitoEntities.SaveChanges();
});
}
var orders = (from myorders in myNexo_ExitoEntities.temp_SubiektOrderList
select myorders).ToList();
foreach (var order in orders)
{
cc2nexo_SubiektOrderList neworder = new cc2nexo_SubiektOrderList();
neworder.Data_utworzenia_sprawy = tryconvert_date(order.Data_utworzenia_sprawy);
neworder.Data_modyfikacji_sprawy = tryconvert_date(order.Data_modyfikacji_sprawy);
neworder.Data_umowy = tryconvert_date(order.Data_umowy);
neworder.Id = order.Id;
myNexo_ExitoEntities.cc2nexo_SubiektOrderList.Add(neworder);
SurroundWithTryCatchDB(() =>
{
myNexo_ExitoEntities.SaveChanges();
});
Debug.WriteLine(neworder.LastName);
}
I am receiving an error
Cannot insert duplicate key row in object 'dbo.cc2nexo_SubiektProduct' with unique index 'K_ID'. The duplicate key value is (1).The statement has been terminated

Answer 1

The reason of problem was SurroundWithTryCatchDB procedure not listed in my question. Because first query caused exception due to unique index all next SaveChanges did not work. I have changed my first query to work with unique values and now everything is OK.